It just has me stumped so far since it's random and when it happens I have zero power anywhere but resets by simply unhooking the battery. I would think no power at all would be the + wire going into the mega fuse block but no juice to the starter either. I may cut the terminal off and put a different one on.
I'd hook a wire to the starter + wire, right at the starter. Insulate it well, and run it up near the battery, and tape it off so it can't short.
Next time it acts up:
Measure the wire added above to ground at the battery terminal. If it measures ~12V, try to start the car, and see what the voltage does.
If it stays at 12v, it's not the wire to the starter, or to the supply side of the megafuse.
Measure the other side of the megafuse, trying not to disturb the wires. If it's not reading the same, it's bad. Adding another wire here for the meter can help.
Then we have the fusebox; but all your problems seem to be everything, and that pretty much ends at the megafuse, for the supply side...
Otherwise, it's going to be ground wires; read the big three article, and go from there.
Be sure to disconnect any wires added for diagnosis. It much easier to add a piece of wire in the driveway, rather than crawling in the mud to wiggle a wire, lol.
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